The present invention relates generally to the field of endodontics and relates more particularly to processes for filling stripped root canals.
Known methods of obturating (filling) an extirpated (stripped) root canal commonly involve the insertion of strand-like pieces of gutta-percha known as points into the root canal and the use of compacting tools known as plungers and spreaders to compact the gutta-percha points within the canal. Typically, the compacting tools are heated to soften the gutta-percha points in the canal and then hand manipulated to progressively feed and compact the points in the canal. Additional points are fed to the canal as the compacting operation progresses in order to fill the canal with gutta-percha.
Another known method of obturating an extirpated root canal involves the insertion of gutta-percha points into the root canal and manipulating the shank of a high-speed, rotating instrument into contact with the gutta-percha points so that frictional heat generated at the instrument shank softens the gutta-percha. With the gutta-percha in a softened condition, it is compacted within the canal with manipulations which include reciprocating motions of the instrument shank.
Limitations associated with known obturation methods relate to the general difficulty in filling of the root canal with filler material so that any voids or fissures associated with the canal wall are filled and the utilization of relatively large and/or high-speed rotating instruments to compact the material within the canal. Unless an endodontist who performs known obturating techniques is highly skilled, all voids and fissures of the canal are not always filled satisfactorily. In addition, reciprocating motions of a relatively large compacting instrument against filler material positioned within a canal increase the possibility that the apical foramen will be extruded by the filler material. Moreover, utilization of any high-speed rotating instrument within a mouth requires a great deal of care to prevent injury to the patient or keep from fracturing the instrument.
It would be desirable to provide a new method for obturating an extirpated root canal with a greater likelihood that gutta-percha compacted within the root canal conforms to the shape of the wall of the root canal and that fissures or similar openings associated with the canal wall are completely filled with gutta-percha.
Another object of the present invention is to provide such a method which obviates the use of large and/or high-speed rotating instruments for compacting filler material within a root canal.
More particularly, the present invention is directed to the obturating of an extirpated root canal with two types of filler material wherein one type of filler material is provided in the form of a gutta-percha point having a predetermined melting temperature and wherein the other type of filler material is provided in the form of a thermoplasticized gutta-percha having a melting temperature of about 15.degree. to 20.degree. C. less than that of the melting temperature of the gutta-percha point. Steps in the method include the introduction of an initial amount of thermoplasticized gutta-percha in a heated, softened condition into the root canal so that the initial amount fills the bottom of the canal. At least a portion of the gutta-percha point is then positioned into the root canal, and another amount of thermoplasticized gutta-percha in a heated, softened condition is introduced into the canal. The another amount of thermoplasticized gutta-percha is then manipulated into contact with the portion of the gutta-percha point positioned within the canal so that the gutta-percha point is fed into and compacted within the root canal with the amounts of thermoplasticized gutta-percha.
Because the thermoplasticized gutta-percha introduced into the canal is a fluid in its heated and softened condition, the apical foramen and any fissures or voids associated with the canal wall are suitably coated and/or filled by the thermoplasticized gutta-percha with no need that filler material be forcibly urged, such as by reciprocating motions of a compacting instrument, into the canal. Thus, the endodontist performing the method of this invention need not possess as high a degree of skill as in prior methods in order to satisfactorily fill the root canal, and the possibility that the apical foramen will be extruded by filler material is reduced by this method. In addition, the heat necessary for softening and rendering workable the gutta-percha point material is absorbed by the point material from the heat of the softened thermoplasticized material. Thus, the method of the invention obviates any need for the manipulation of a high-speed rotating instrument within the canal for the purpose of generating frictional heat.
A more complete understanding of the present invention will be had by reference to the specification and accompanying drawings wherein like numerals refer to like parts throughout.